1. Field of the Invention
The present invention relates to novel antipathogenic peptides, to DNA sequences encoding said peptides, to vectors comprising said DNA sequences, to transgenic plants comprising a DNA sequence encoding said peptides, to compositions containing anti-pathogenic peptides and to the use of said peptides and compositions for controlling plant pathogens. Also comprised are methods of preparing antipathogenic peptides or compositions containing same and transgenic plants able to synthesize anti-pathogenically effective amounts of said peptides.
2. Description of Related Art
Peptides showing antipathogenic and especially antimicrobial activity are already known in the art. Specifically of importance are the so-called lytic peptides, some of which are known to be active against a broad range of organisms while others produce little or no effect There are many examples of lytic peptides from animal, plant, insect and microbial sources including the mammalian defensins, cecropins, thionins, mellitins, insect defensins, magainins, attacins, dipterins, sapecins, caerulins, xenopsins, or hybrids thereof. The amino acid sequence of several lytic peptides with antimicrobial activity are disclosed in WO 89/04371. Lehrer et al. (1986) disclose six antimicrobial peptides (AMPs) from rabbit granulocytes that are structurally homologous to human neutrophil defensins. Three of the rabbit AMPs (NP-1, NP-2 and NP-3a) are disclosed to be effective against Candida albicans.
Another class of peptides with antipathogenic activity is represented by hydrolytic enzymes, such as chitinase and .beta.-1,3-glucanase, which are known to inhibit fungal growth (Schlumbaum et al., 1986; Mauch et al., 1988).